Dissolved oxygen (DO) concentrations of the fully marine Lough Hyne, SW Ireland, were sampled in biologically different habitats between 2014 and 2019 to investigate the declining water quality in the marine reserve and the severity of oxidative stress on benthic communities. DO was measured above and below shallow subtidal rocks, in the Rapids connection to the Celtic Sea, in seagrass meadows (Zostera marina), and at various water depths (1–15 m) in the South Basin. DO values above rocks were normoxic to hyperoxic in daytime (7.8–17.3 mg l⁻¹); below rocks were often hypoxic (0.24–2 mg l⁻¹). South Basin sites experienced hypoxia less often than the North Basin, except for the Goleen, presumably due to differential current flow. DO fluctuations occurred in spring (before ephemeral macroalgae proliferate), summer (when algal mats smother the benthos), and autumn (when macroalgae decay). While the Rapids were normoxic, the seagrass meadows below them exhibited periodic DO stress. Labhra Cliff (9–14.5 m) was normoxic to hyperoxic in autumn but experienced suboxic and hypoxic events in summer. Many organisms in Lough Hyne are experiencing periods of hypoxia below their published sublethal limits, the effects of which could be exacerbated by periodic hyperoxia.

中文翻译：

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从上方受到压力，从下方受到压力：半封闭海洋湖海恩河中的溶解氧波动

在2014年至2019年之间，在生物学上不同的生境中采样了爱尔兰西南部爱尔兰全海区Lough Hyne的溶解氧（DO）浓度，以调查海洋保护区水质下降和底栖生物群落氧化应激的严重性。在浅海潮下岩石的上方和下方，在与凯尔特海的激流连接处，海草草甸（Zostera marina）以及南盆地的各种水深（1–15 m）处测量了DO 。白天，岩石上方的DO值从高氧到高氧（7.8-17.3 mg l ^-1）；岩石下面通常是低氧的（0.24–2 mg l ^-1）。除了戈林以外，南部盆地地区发生缺氧的频率要低于北部盆地，这可能是由于电流差引起的。DO的波动发生在春季（短暂的大型藻类扩散之前），夏季（藻类席卷底栖生物时）和秋季（大型藻类腐烂时）。尽管急流是常氧的，但它们下面的海草草甸却表现出周期性的DO应力。Labhra Cliff（9–14.5 m）在秋季为高氧至高氧血症，但在夏季经历了亚氧和低氧事件。海恩海恩地区的许多生物体正处于低于其已公布的亚致死限度的缺氧时期，周期性的高氧血症可能加剧这种效应。